9 1/2 Evinrude Runs Great at 3/4 Choke Dies With No Choke

[Brad S]

Have a 1968 9 1/2 hp Evinrude Sportwin. Runs good at 3/4 choke. It will idle smoothly. When I open the choke all the way it wants to die unless I am at 3/4 throttle or more. Has new gas and oil mixture at 50:1. Motor has sat for 2+ years. At 3/4 choke it starts on the 2nd or 3rd pull when cold and 1 pull when warm (at 3/4 choke with the throttle in start position.) Can I run Seafoam through the carburetor or do I need to rebuild the carburetor and/or rebuild the fuel pump?

 

[F_R]

Re: 9 1/2 Evinrude Runs Great at 3/4 Choke Dies With No Choke

First try opening the slow speed needle a bit. If that doesn't work, clean the carburetor

 

[Brad S]

Re: 9 1/2 Evinrude Runs Great at 3/4 Choke Dies With No Choke

Thanks for the advice. Going to rebuild the carburetor. Is there a rebuild kit available for the fuel pump for this motor? It is 1968 9 1/2 hp evinrude model 9822E? The fuel pump for the 9.9 looks like the same one. Are these fuel pumps interchangeable?

 

[geoffwga1]

Re: 9 1/2 Evinrude Runs Great at 3/4 Choke Dies With No Choke

Thanks for the advice. Going to rebuild the carburetor. Is there a rebuild kit available for the fuel pump for this motor? It is 1968 9 1/2 hp evinrude model 9822E? The fuel pump for the 9.9 looks like the same one. Are these fuel pumps interchangeable?

I wouldn't worry about the fuel pump for now,concentrate on the carburettor.Soak it overnight in carb cleaner ,then wash off with hot soapy water and blow dry with compressed air.Pay particular attention to passages under core plug/s.
This carb is a different shape to all the others but the basic principles are all the same,just laid out differently.
Geoffwga1.

 

[awiger25]

Re: 9 1/2 Evinrude Runs Great at 3/4 Choke Dies With No Choke

Hi, I had a similar problem with my 72 sportwin 9.5.. It would run but when i hit the choke, rpms would increase drastically. I had the carb gone through but it was clean so next we turned to the fuel pump. Upon further inspection, we found the entire pump was in shambles. If the carb rebuild didnt work, I would take a look at the fuel pump!